Production Data Analysis for Commingled Multilayer Gas Reservoirs

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractMost of the major unconventional gas plays in the U.S. have multiple productive intervals. Wells are completed with multiple fracture treatments, and are produced commingled. An earlier paper 1 described a single-well, multilayer, analytical reservoir simulator * for estimating individual layer properties in multilayer unconventional gas reservoirs by automatic history matching production and spinner survey data simultaneously. The present paper describes several interactive graphical aides that greatly facilitate the history matching process when used in conjunction with the analytical, multilayer reservoir simulator. These graphical tools include an allocation graph and layer and cumulative production log graphs. These graphs allow the engineer to quickly review the quality of the match at any point during the history matching process.Use of these graphical tools has improved the history matching workflow to the point that a complete history match of a well with 20 frac stages, two years of daily production, and three spinner surveys can be performed in as little as four to six hours, from construction of the initial data set through completion of the final match.